Simulated-use validation of a sponge ATP method for determining the adequacy of manual cleaning of endoscope channels

Table 3 Comparison of residual ATP detected by the direct sponge method versus level of residual protein and viable count in colonoscope instrument channels

	Sponge sample^b (N = 3)	Flush sample^c (N = 3)
Test parameter^a	RLUs (Std)	Protein μg/cm² (Std)	E. faecalis Log₁₀ cfu/cm² (Std)	P. aeruginosa Log₁₀ cfu/cm² (Std)
Positive control Soiled but no cleaning	9747.00 (436.48)	335.4 (65.55)	6.782 (0.212)	6.669 (0.192)
Partial clean Soiled, 50 mL water flush and no brushing	6601.00 (1684.00)	3.99 (3.16)	5.254 (0.142)	4.476 (0.253)
Full cleaning Soiled, cleaned pre-HLD	29.00 (36.39)	0.23 (0.07)	0.787 (0.364)	1.608 (0.269)
Negative control Soiled, cleaned post-HLD and storage	14.00 (21.66)	0.04 (0.07)	0.025 any organism (0.090)

^aData for each test parameter represents the average and standard deviation (Std) of three replicate endoscope tests (N = 3)
^bATP was measured as relative light units (RLUs)
^cThe protein and viable counts were done on a parallel set of colonoscopes that were soiled in the same manner and were harvested using the flush method of sample collection

ISSN: 1756-0500